Hi
@tufanv
when you say "old version" what do you mean?
I sent my app a first time (refused) a second time with your suggestion (refused).
Every time the email that Apple sends me always has the same indication:
SDK Version Issue - This app was built with the iOS 11.2 SDK. Starting March 2019, all iOS apps submitted to the App Store must be built with the iOS 12.1 SDK or later, included in Xcode 10.1 or later.
(my app is not an update but a new app)